The number of young physicians choosing a career as a physician-scientist has declined dramatically over the last thirty years. To address this deficiency, we established an intense three-year laboratory-based training program, referred to as the Physician- Scientist Research Training Program (PSTRP), at the University of California, San Diego, School of Medicine. The program is specifically designed for physicians who have completed their clinical training, with no clinical obligations during the research training. The first class entered the program in June of 2000, and by several criteria, the program has been highly successful: of the 19 trainees who have completed the program, 11 have appointments in academia or the biotechnology community, four are on track to be promoted to Associate Professor within the next year, and together they have published 163 papers, or 8.6 papers per trainee. Sixteen faculty members, including two from the Salk Institute, serve as research mentors with their research areas corresponding to those of the mission of the National Institute of Diabetes and Digestive and Kidney Diseases. The faculty members are highly experienced, well- funded investigators with a strong track record for serving as a research mentor. The present proposal requests continuation of the program with two training positions at each level, for a total of six training positions.